1 Field of the Invention
The present invention concerns a fast vertical trajectory prediction method for air traffic management (ATM), and relevant ATM system.
More in detail, the present invention concerns a method which is able to calculate the vertical trajectory of an aircraft, by integrating in a suitable way numerical solutions and analytical solutions for some flight phases, in a fast and computationally effective way. The present invention further concerns an ATM system implementing the method of the invention.
2 Description of Related Art
ATM systems are currently supporting flights. However, the relevant international traffic is increasing rapidly [4,5] and the need is felt for an ATM systems that support a number of flights that is much larger than the one of current operative systems.
Therefore, the automation level in ATM processes must be increased to fulfill this requirement. The number of aircrafts that are planned to fly in the next generation airspace would require a non realistic number of human controllers [6]. As a consequence, software controllers would replace human ones in the main function such as conflict resolution.
Several tools are under development to support the implementation of safe software controllers. Indeed, some functions require running complex algorithms with a heavy computational load. Moreover, since a real time solution is needed, these algorithms should be adequate to ensure the output of a solution in a short time. In particular, uncontrolled loops must be avoided, since they prevent the system to fulfill the requirement for time determinism.
An important class of tools that are needed for future airspace management are conflict resolution systems [4,5]. They need to be supported by accurate trajectory prediction algorithms to generate realistic solutions for detected in-flight congestions. In the last few years, several tools have been developed to provide effective trajectory prediction [7-11]. The main issues related to the realization of a proper trajectory prediction tool are:    i. The tool must be capable to support real-time conflict resolution, i.e. thousands of runs must be performed in few seconds;    ii. The tool must be based on the knowledge of parameters included in an aircraft database that covers all managed traffic and that is updated as soon as a non negligible number of new aircraft models is introduced in the market.
To ensure that condition i) is satisfied, the trajectory prediction computational engine must be reduced so that it performs the minimum number of needed computations to generate a solution.
Regarding condition ii), the worldwide standard database that was selected as reference in most of the ATM tools that have been developed in the last few years is BADA™ developed by Boeing™ Europe for EUROCONTROL™. The version 3.6 included all parameters needed to integrate aircraft altitude and speeds with the 99% coverage of all aircraft operating in Europe up to year 2006, and the majority of aircraft types operating across the rest of the World [11].
The following journal articles are related to the same field of automation of ATM systems:                Slattery, R. and Zhao, Y., “Trajectory Synthesis for Air Traffic Automation,” AIAA Journal of Guidance, Control, and Dynamics, Vol. 20, Issue 2, March-April 1997, pages 232-238;        Swenson, H. N., Hoang, T., Engelland, S., Vincent, D., Sanders, T., Sanford, B., Heere, K., “Design and Operational Evaluation of the Traffic Management Advisor at the Fort Worth Air Route Traffic Control Center,” 1st USA/Europe Air Traffic Management Research and Development Seminar, Saclay, France, June 1997;        Glover, W. and Lygeros, J., “A Stochastic Hybrid model for Air Traffic Control Simulation” in Hybrid Systems: Computation and Control, ser. LNCS, R. Alur and G. Pappas, Eds., Springer Verlag, 2004, pages 372-386;        Marco Porretta, Marie-Dominique Dupuy, Wolfgang Schuster, Arnab Majumdar and Washington Ochieng, “Performance Evaluation of a Novel 4D Trajectory Prediction Model for Civil Aircraft”, The Journal of Navigation, Vol. 61, 2008, pages 393-420.        
It is worth noting that none of the above articles reports about a real-time implementation of trajectory prediction for the automation of the current form of Air Traffic Management System.